We can be invisible??!!

Yes - and soon, according to Natural History Magazine. But how?

First understand that light is one of many types of 'waves' (essentially bundles of mobile energy). Light is the one wave which, by bouncing off objects, makes objects visible to humans.

Light, as we know, travels at an incredible speed (186,000 mps). When it travels through different mediums, particularly those denser then air (e.g. water), it slows down. The slowing down of light is observed by it bending - a phenomenon known as 'refraction'. Anyways, the more dense the material, the more light slows down, and, consequently, bends.

Through the use of specially engineered 'metamaterials', scientists at Duke University have been able to bend light beyond what was considered possible (see video). As of now, they have created objects which become completely invisible, save for the casting of a small shadow.

With ongoing research in the field, maybe one day we'll be able to get a cloak like Harry Potter!